A plurality of semiconductor integrated circuits formed on a semiconductor wafer undergo an electrical test before being separated into respective chips to determine whether or not they are manufactured in accordance with the specification. In this electrical test, an electrical connecting apparatus including electrical test probes to be coupled to electrodes of devices under test that are the respective semiconductor integrated circuits is used. The devices under test are coupled to electrical circuits of a tester via this electrical connecting apparatus.
As one of conventional probes used for this electrical connecting apparatus, there is one including a plate-like probe main body portion and a probe tip portion provided on the probe main body portion to contact on an electrode of a device under test (for example, refer to International Publication WO2006/075408, which is incorporated by reference). The probe main body portion has a rectangular attaching portion attached to a probe board, a connecting portion extending downward from one side of the attaching portion, a pair of arm portions extending in a front-back direction from the connecting portion below the attaching portion, and a pedestal portion formed integrally with the arm portions so as to combine tip ends of both the arm portions. Also, the probe tip portion has a coupling portion coupled with the pedestal portion by being buried or fitted in the pedestal portion and an extending portion continuing into the coupling portion and extending downward from the pedestal portion.
According to the probe in International Publication WO2006/075408, it is proposed that the probe main body portion should be made of a highly resilient conductive material, and the probe tip portion provided at a lower end of the pedestal portion of the probe main body portion should be made of a metal material with excellent hardness. By forming the probe main body portion by the highly resilient metal material, elastic deformation of the arm portions of the probe main body portion is enhanced when the probe tip portion of the probe is thrust to the electrode of the device under test, which enables the probe tip portion to couple the electrode appropriately and reliably.
Also, when an overdriving force that causes the aforementioned elastic deformation at the arm portions acts on the probe, a probe tip of the probe tip portion slides on the electrode along with the elastic deformation of the arm portions. By forming this probe tip portion by the highly hard material, abrasion of the probe tip is suppressed, and durability of the probe is enhanced.
Meanwhile, in a case where multiple chip areas on a wafer undergo an electrical test per chip area in several batches with use of the electrical connecting apparatus including the aforementioned multiple probes, the probe tips of some probes that deviate from the chip area may sometimes contact a tilting edge of the wafer in a state where the overdriving force acts on the probes. In such a case, when the probe tips are guided outward along the tilting edge of the wafer, the probe tip portions of the probes will receive a bending force. Also, when the probe tip of the probe contacts an edge of an opening edge portion, which exposes the electrode, of a passivation film covering a surface of the semiconductor wafer, the probe tip portion may sometimes receive a similar bending force.
These bending forces may act on a border portion between the pedestal portion of the probe main body portion and the extending portion extending from the pedestal portion and cause breakage of the probe tip portion at the border portion. In the probe in International Publication WO2006/075408, since the border portion between the extending portion and the pedestal portion is in a linear manner, the bending forces will act on the linear border portion, especially a central area thereof, in a concentrated manner when the bending forces act on the probe, which may lead to breakage of the probe tip portion.
As one of the electrical test probes that prevent such breakage of the probe tip portion, there is an electrical test probe provided with a reinforcing member at the border portion between the pedestal portion and the extending portion (Japanese National Patent Appln. Public Disclosure No. 2008-82718, which is incorporated by reference).
In this electrical test probe, when a bending force that deforms the probe tip portion toward the probe tip reinforcing portion acts on the probe, the probe tip reinforcing portion receives part of the bending force to decrease the bending force acting on the border portion and brings about a reinforcing effect on the probe tip portion.
However, in this conventional technique, the bending force acting on the border portion between the extending portion and the pedestal portion is decreased, but a new bending force acts on a border portion between the extending portion and the reinforcing member. Thus, the probe may be broken at the border portion between the extending portion and the reinforcing member.